July 19, 2024

Jackie Pinchbeck

Global Connectivity

Blockchain: A Beginner’s Guide (Part 11)


Blockchain is the technology behind Bitcoin and other cryptocurrencies. A blockchain, or distributed ledger, is a decentralized database that records transactions across many computers so that the record cannot be altered retroactively without alteration of all subsequent blocks and the collusion of the network.

Blockchain: A Beginner’s Guide (Part 11)

Blockchain: A Beginner’s Guide (Part 11)

Blockchain is a technology that allows the transfer of digital information without the need for an intermediary. This makes it possible to share data in a secure way, without having to rely on third parties such as banks or other financial institutions.

Blockchain technology is often referred to as being “decentralized”, which means there’s no central authority controlling it–it exists across multiple computers on a network instead. When you add new data into this type of database system (i.e., write something), each computer on the network must verify and agree with each other that it hasn’t been tampered with before adding its own copy of this piece of information into their version of the ledger too. This process helps make sure that no one can forge transactions since everyone will know if someone tries!

What is Blockchain?

Blockchain is a digital ledger for recording transactions. It is a distributed database that maintains a continuously growing list of data records, called blocks. Each block contains a cryptographic hash of the previous block to ensure data integrity and chronological order of the block content. The blockchain database isn’t stored in any single location or managed by any one person or organization; instead, it exists on multiple computers around the world (known as nodes), each with access to their own copy of all transactions ever made using Bitcoin or other cryptocurrencies.

This makes it possible for individuals who do not know each other to create an irrefutable record without having trust in one another beforehand–and without relying on any central authority figure like a bank manager or government official!

The Difference between Public and Private Blockchains

Public blockchains are open to everyone and anyone can participate in them. This means that you don’t need to trust anyone when using a public blockchain because no one can control or manipulate the network. You can see this with Bitcoin, for example: if you have some bitcoin and send it to someone else, there is no way for anyone else to stop that transaction from happening unless they control more than half of all hash power on the network (which is unlikely).

Private blockchains require some level of trust between participants as well as within themselves; however, they aren’t necessarily centralized like traditional databases are (in fact many people argue that private blockchains should actually be called distributed databases).

Consensus Protocols and Mining

A consensus protocol is a method of reaching agreement on the state of a shared ledger. The different types of consensus protocols use different methods to achieve this goal, but they all have one thing in common: they need some way to prevent bad actors from changing the data on their own copy of a blockchain.

The most popular consensus algorithm used today is Proof-of-Work (PoW), which was first introduced by Bitcoin in 2009. In PoW systems, miners compete against each other to solve complex mathematical puzzles that require large amounts of computational power and electricity–a process known as “mining.” Mining allows miners to create new blocks on top of previous blocks and add them into the chain until there are so many that no more transactions can fit inside them (at least not without exceeding block size limits).

Proof of Work (PoW) vs. Proof of Stake (PoS)

Proof of Work (PoW) vs. Proof of Stake (PoS). These are two different ways to reach consensus on a blockchain network, which means they’re also two different ways to secure the network and prevent bad actors from double spending or otherwise manipulating the blockchain.

The first thing to know is that both PoW and PoS require you to use some amount of electricity; however, in general, PoW is far more energy efficient than PoS because it requires miners who are constantly solving complex mathematical problems in order to create new blocks on the chain–this requires significant computing power which requires significant electricity consumption! On the other hand, with Proof-of-Stake systems like those used by Cardano or NEO no such heavy lifting is required: instead users stake their coins against each other in order for them not only earn rewards but also vote on what should go into each block being created at any given time

Hash Functions in Blockchain Technology

Hash functions are also used to ensure that transactions are valid. Every block has its own unique hash, which is created from the transactions within that block. This ensures that each transaction can be verified independently of other blocks in the blockchain, and prevents users from accidentally spending their coins twice (or more).

Blockchain is the technology behind Bitcoin and other cryptocurrencies.

Blockchain is a distributed ledger technology that was invented in 2008 to serve as the public transaction log for Bitcoin. It’s basically an immutable, decentralized database that records all transactions on its network.

In addition to being used for cryptocurrencies like Bitcoin, blockchain has many other applications including payment processing, supply chain management and healthcare record keeping.


Blockchain is the technology behind Bitcoin and other cryptocurrencies. It’s a decentralized database that stores information in a way that makes it difficult to tamper with. There are many different types of blockchain, including public and private ones. They all work in similar ways, but they have different pros and cons when it comes down to security and privacy concerns.